Fire-resisting cabinet.



0. H. L. WBRNIGKB.

HRB RBSISTING CABINET. APPLICATION FILED NOV. 11, 1913.

1,096,479. i n Patented 1v1y12,1914.

2 SHEETS-SHEET 2.

UNITED sTATEs PATENT oEEIoE.

OTTO H. L. WERNICKEyOF GRAND RAPIDS, MICHIGAN, ASSIGNOB. TO THE MACEY CO., OF GRAND RAPIDS, MICHIGAN, A CORPORATION F MICHIGAN.

FIRE-RESISTING CABINET.

Specification of Letters Patent.

" Application led November 11, 1913. Serial'No. 800,370.`

ratented May 12, 1914..

' which has been extensively adopted into commercial use within. the past few years because it is inexpensive and capacious, and

light weight compared with the ordinary safe containing more or less massive msulation, in which the exothermic action of heat isobjectionable because of. the danger thereof to the safe-contents. i

The more important advantages which it has been the aim of manufacturers of this type of safe to attain are low cost, lightness in weight andl etliciency in retarding heat. For the last-'named attainment, organic materials,` such as straw, strawboard, and the like, and linorganic materials, such as asbestos, plaster of Paris, and the like, have been-employed forliningoriilling the spaces between the safe-walls. These, however, in the various forms in which they have been 'providedhhave proved insufficient for their firepro'oiing purpose, since while they have l been found to resist an eXt-raordinarydegree of heat, they do so only for a short time, ranging from about five minutes upto, possibly', thirty minutes under temperature ranging from about 1000"1?. to about 2000 F.; and the gases generated by the action of the heat on theinsulating materials tend to distort the'sheet-metal walls and thereby admit destructive heat to the safe-contents.

The primary `object of my invention is` while retaining the important advantages of low cost and light weight ofthe structure, to provide a form `of insulating materialof the kind referred fk5, in the space between the sheet-metal safe-walls, which' shall serve .to greatly enhance, over such insulation as hitherto used for the purpose, tbe retardation of heat through the Walls.

In the accompanying drawings, which 'illustratemy invention in a preferred form of its embodiment, Figure 1 is a View in plan sectlon of a safe provided with my improvement; Fig. 2 ,is an. enlarged, broken lperspective view showing my improved in sulation provided as a filling for the space between the safe-walls, and Fig. 3 is an enlarged view of the construction of seam employed for yieldindly joining the rear wall and side walls of the safe. l

The inner walls 4 and outer walls `5 of the entire structure, including those of the hingedly-folding doors (i, are formed `of sheetmetal 'and spaced apart, as shown. Detailsof construction shown inFig. 1 require noA description in this connection, since they form no part ofthe present invention.

The spaces between the Walls are provided with a filling 7, extending from wall to wall, of strawboard, each board comprising a central corrugated section 8 between outer fiat sections V9, which are 'coated on their outer surfaces with alight, absorbent, incombustiblel material 10 containing water of crystallization, suchjas gypsum', which may beapplied in suspension or solution with a brush, to the thickness of about one-sixteenth of an inch, more or less; and the strawboard` is previously treated, by ,immersion-'on otherwise, and subsequent drying, with a deliquescent substance, such asl a solution of chlorid of calcium or maghesium.` While the substances specified are preferred for my purposefother chemical substances having similar properties may be usedi The result is a light-weight, low-cost insulator of -su-r peri'or heatfretarding properties. The corrugat'ions inthe strawboard, or other forms of interstices to render it light, provide `a multiplicity of dead-air spaces distributed throughout the filling; and the light organic structure, when coated with the porous inorganic material, is stable and will not shrink under the influence of heat, but lls the space between the walls and requires no means of attachment thereto nor bracing. f

ln case of tire, water distilled bythe heat. from the outer layers of inorganic and `or-y ganic materials is absorbed iby the next lay-ers, whereby the water acts. as a ,wet blanket on such next, until the moisture vaporize'd from the preceding layers is combined and taken up by the strawboard of the next succeeding layer; and the vaporization thus progresses, While the heat continues, from the outermost layers through the entire filling. Thus each layer progressively absorbs the moist vapors released from the preceding layer by the progress of the destructive distillation of the organic material and release of the Water of crystallization, until finally the straWboard of the inner layers becomes Wet and soggy. In that condition of the light, corrugated strawboard it would mash and collapse, Were it not for the relatively-thin alternating coatings 10 and the absence of large voids or of a large dead-air space in the structure. Moreover, the coatings 10 being distributed throughout the filling prevent collapsing of the structure which, in case of fire, provides alternate layers of the strawboard for carbonization by the heat, if it be sufiiciently intense and enduring, after distillation of the moisture; and the carbonized strawboard, which is itself a good heat-retarder, is held intact by the coatings against crumbling.

By the deliquescent treatment of the 0rganic material of the safe-lining, its insulating action is materially increased, since the amount of Water to be vaporized by heat is greatly augmented, andthe lining-structure produces progressive accumulation, absorption, and revaporization of this moisture, thereby increasingly checking the progress of the heat through it. The coatings l0, moreover, besides exerting on the strawboard the sustaining effect referred to, contribute from their contained Water of crystallization additional vapors to increase thel yield of moisture from the lining under the act-ion of heat in case of fire.

The. seams 11 formed of interlocking joints between the adjacent edges'of the outer rear wall and side-Walls of the safe, while sufficiently tight to be proof against the admission from Without of dangerous quantities of air into the zones of highest temperature inthe filled spaces, whichv might ignite or explode gases generated therein, are loose enough to permit the eX- panding gases of the superabundance of moisture, as steam, to escape and thus prevent such accumulation of the pressures as would tend to distort the Walls and admit the heat into the interior of the safe to injure or destroy its contained papers, fabrics ,and the like delicate contents. In this connection it should be borne in mind that While the temperature to which a safe is subjected in a fire seldom, according to underwriter experts, exceeds the temperature of 15000 F.. the exothermic after effect from the safe itself or debris often continues for hours at` destructive temperatures. Obviously. therefore, where insulating materials of great volume, density and conducthe heat to the contents of the safe, and to bring about the destructive distillation with a certain amount of resultant Water-vapor a comparatively high temperature is required. By rendering the organic material employed deliquescent and coating it with organic material containing much Water of crystallization, While the temperature necessa ry to cause destructive distillation does not change appreciably, if at all, the amount of heat required to raise the material to the temperature required for effecting the distillation is considerably increased because lthe vapor of Water combined with or taken up by the chemical requires heat to drive it ofl" before that heat can begin to act with destructive effect upon the organic matter. The Water-vapor formed both from the decomposition of the chemical and, later, from the destructive distillation of the organic matter and the added water released from the organic matter, holds and retards the temperature at or near the boiling point of water until these vapors are driven ofi'.

I realize that considerable variation is possible in the details of construction thus 'specifically shown and described, and I do not intend by illustrating a single, specific or preferred embodiment of my invention to be limited thereto; my intention being in the following claims to claim protection for all the novelty there may be in my invention as broadly as the state of the art Will permit.

What I claim as new and desire to secure by Letters Patent is Y l. An insulating filling for fire-resisting cabinets, comprising a plurality of layers of organic material, the outer surfaces of each of said layers being provided with a sustaining coating of inorganic material, and intermediate layers connecting said outer surfaces and formed to provide air spaces between said outer surfaces.

2. An insulating filling for Vfire-resisting cabinets, comprising sheets of corrugated straw-board provided with outer fiat surfaces, with sustaining coatings of inorganic material applied to said fiat surfaces.

3. An insulating filling for fire-resisting cabinets, comprising corrugated sheets of or-J ganic material provided with outer flat surfaces, with sustaining coatings of inorganic vided on its outer Hat surfaces with sustainmatelal applied to sfzixld atfsuraces. ing coatings of inorganic material.

` 4. n insulating l ing or e-resisting WE cabinets, comprising sheets of corrugated or v OTTO. H L' RNICKE' 5 ganic material provided with outer flat sur- In presence ofv faces and chemically treated to augment its F. A. MQNTELIUS,

natural water-absorbing capacity, and pro- G. H. CURRY. 

